This invention relates to an electrical hydraulic jack, particularly to that type having improved transmission and driving mechanisms for simplifying the structure and facilitating operations.
Conventionally, jacks are usually classified into two types--the screw type and the hydraulic type. The former is seldom used today while the latter prevails in the mechanic field and presents with various designs among which the electrically actuated hydraulic jack is the one widely accepted by the users concerned with this device. However, the known electrical hydraulic jacks usually have a complicated structure which suffers not only a high manufacturing cost but also an inconvenient operation. Typical hydraulic jack of this kind is U.S. Pat. No. 2,034,605, which has a telescopic lift strut structure matched with a motor driving mechanism for being electrically actuated through the power source of the motor vehicle. However, the configuration of this known hydraulic jack is much complicated, and the structure is bulky, not convenient for practical use.